Center-bonded mounts provide flexible suspension systems joining supported members. Although generally intended to carry loads in the axial (e.g., vertical) direction, the center-bonded mounts are capable of supporting static loads in both axial and radial directions while isolating vibrations and withstanding shocks in all directions.
Typically, a cushion of elastomer, which is bonded to the periphery of tubular sleeve, fits within a hole formed through the support member. One end of the elastomer forms a spacer between the supported member and one side of the support member. The other end of the elastomer includes a rebound tail that spreads under compression to engage the other side of the support member. A bolt, which extends through the support and supported members, the two washers, and the tubular sleeve, compresses the elastomer between two washers filling the hole in the support member, squeezing the opposite sides of the support member, and spacing the support and supported members. Tightening the bold draws the two washers against opposite ends of the tubular sleeve for assuring that the elastomer is properly pre-compressed between the support and supported members.
The elastomers behave similarly to coil springs with added damping (hysteresis) based on the molecular structure of the elastomer. The center-bonded mounts exhibit both axial and radial stiffness. However, the axial and radial spring rates are generally not independently controllable.